/Engine/Source/Runtime/StaticMeshDescription/Public/StaticMeshOperations.h
If the given minimum resolution is not enough to handle all the charts, generation will fail.
UV layout correctly generated
static bool CreateLightMapUVLayout ( [FMeshDescription](API\Runtime\MeshDescription\FMeshDescription) & MeshDescription, int32 SrcLightmapIndex, int32 DstLightmapIndex, int32 MinLightmapResolution, ELightmapUVVersion LightmapUVVersion, const [FOverlappingCorners](API\Runtime\MeshUtilitiesCommon\FOverlappingCorners) & OverlappingCorners )